Andrew, I wouldn't worry about what anyone is thinking - you have absolutely every right o demand perfection from audio system.

I would have the sub replaced by Merc, then get yourself to the very best 3rd party audio installation shop you can and have a pro opinion. Have them identify the route cause and write a letter confirming it.

I'd then ask them about remedial action and present Merc uk with the bill for doing so...

I had a very similar issue once and it was that the phasing / polarity of the sub was incorrect.
There was an issue with the wiring loom and it was cabled incorrectly.
The outcome was that the cone was "firing" in the wrong direction. Not only was this causing a distinct lack of bass, but was distorting too.

Not saying thats the issue here, but certainly worth them looking into it.

I would be very interested to know if the sub is clipping due to too much power in, or if it's a signal issue. So first things first, can you get to the wires into the sub? Swap the buggers around. Might immediately resolve it. Subs tend not to like being asked to play backwards!

Next, do you know... is it an IB (infinite baffle) jobbie or does it have a sealed box.
The next thing I'd want to do would be simply throw another similar specification sub in there and see if the issue persists. So if it's sealed, something like a JL Audio 10W3 is likely to be of a similar specification (Or indeed just one of the better Alpine or JBL 10s )

If that new sub sounds similar, you could be looking at a few things. Signal interferance, the "sealed" box not being sealed properly (if it is) or a number of other things.

I would have to hear it though to have any ideas.

One person not too far from you mate who I'd give a very strong personal recommendation to get to the bottom of this is Lee at PlatinumInCar, Coventry. Book it in and tell him you don't understand why the subs sound so poor. See what he thinks. He does some seriously brilliant bespoke work and I'd strongly recommend him.

Down my way, the shout out would go to CarAudioSecurity. Autocapital are always recommended but they to be honest are cowboys (IMHO!!!! Libel aside.. ) who simply overcharge due to the penchant for Ferarri to drop their cars there for work

I would never ever put up with poor quality sound but the difference is; in the cars I've picked up I've always expected it - which is why with every car I've ever owned more than 4 or 5 months I've ripped the whole lot out and put my own gear in

One last thought.. Is there really no one complaining about this issue?

In that case can we be sure that it isn't simply a case of whoever is retrofitting these cars with B/O systems doing a crap job? I doubt they come from the factory with the system fitted. I bet theres a UK car audio distributor doing the work. Maybe the other one you heard is shite because it was fitted by the same cowboys. Just one thought.

Maybe get a good quality audio recorder out and upload it on an american based SLS owners forum, see if you get anywhere.

Or for that matter - the arabic enthusiast forums would be a reasonable shout too if need be.

Guys, thanks so much for all the recommendations and comments - it's far to say that I do feel a little silly moaning about the stereo in an SLS, but the reality is that it's an important aspect for me.

It's particularly jarring because I've been here before...the Maserati . Not the standard Bose sound system - that was just shit. Hardly any bass at all! But, what bass it did have categorically did not distort. Then, I spend upwards of 3k replacing the system with what were supposed to be very expensive components. And on the whole, the quality of sound was awesome....until such point that I added a bit of bass and turned up the volume. At that point, the JL 10W3 sub would make exactly the same vibrating noise that the subs are doing in this SLS! I took it back to the installer (The Sound Gallery, High Wycombe) who checked everything was wired correctly, listened to my music and how well the bass sounded in the Mini we had at the time and basically just told me to turn the bass down.

Now, I'm not being funny but I'm hardly asking too much when the Mini's HK system could chuck out harder hitting lows without distorting and this system couldn't! I was unhappy but they came up with some sort of excuse that the enclosure on the rear shelf wasn't the best place for a sub (but yet it seems no problem locating the sub in our E-class in this place and that sounds perfectly nice).

So, quick question for Mega (or any other expert)....with such a quality sub fitted in the same location of the factory sub, why would it distort like that? What I can say is that it was a tight fit - they had to bolt a 1-inch thick piece of wood to the panel and mount the sub on that, not only for strength but to give clearance for the depth of the sub (It still fitted comfortably below the shelf). Yet despite all that, the cone would vibrate like it was being overpowered, yet couldn't deliver a hard enough hitting low for my liking. And I'm comparing this to relatively standard factory-fit systems!!

Anyway, the distortion in the SLS is almost identical to that and makes me think that maybe the location does have something to do with it? Whilst this has clearly distressed me this weekend, I'll have to wait and see what it's like when the dealer have replaced the sub....but let's be honest, with another SLS sounding identical, it's unlikely to be any better.

But I won't let that put me off the car (not just yet anyway); it's too fine a machine in every other respect for that! So, the next step is a high-end installer (thanks Mega for the recommendation in Coventry - they will be my first port of call)....although it's fair to say my confidence in the aftermarket (both installers and product) is severely dented after the Maserati experience described above.

I am prepared to chuck whatever is required to make this work...as long as I can utilise the existing space and retain the (very, very good) tweeters atop the dash. I don't want anything adding outside of the factory spaces or anything modified visually so, my hope is that there'll be products that will allow me to retain most of the good bits of the existing system and just replace the two subs (yes, it has two in the rear shelf) for ones that work to my satisfaction (hell, they only need to reach the standard of a typical factory-fit HK system for me to be delighted!).

The funny thing is, I nearly didn't check the audio system before I bought the car as I honestly thought the B&O (especially at £5k+!) would be the very best and would deliver all I could ever ask for!

Finally, in answer to a few of your helpful responses, a couple of you have mentioned whether the speaker polarity is correct. However, given factory-fit systems all utilise one-way connectors, I'd be surprised if these could be fitted the wrong way round . Also, with another SLS sounding exactly the same, whats the chances of them both having been wired incorrectly?

Also, Mega....this is 100% a factory-fit option, and one that is a well documented as being integral to the car right from the development stage! B&O reckon they were involved in the development of the car to get the right speaker positions and did thousands of km's of tests to ensure they got it just right. This is why I'm so confused as to why both examples I've heard are so shit. Also, I've searched and searched...and searched again and, apart from just ONE other post from 2 years ago from a guy in the US, there is nothing anywhere online from anyone else complaining about this. Really very odd....but then I've sat in two cars which sound shit and I guess the previous owners of these just spec'd the option because it was 'the best' and probably didn't know what they were hearing (if indeed they used it at all).

When I get my car back, if it's no better I will try and make a recording so you can all hear this and see what you think!

There might not be much info on it because theres not that many SLSs around?? In any-case if I was spending that much on a car I would expect every thing to be perfect..stilll I bet the engine sounds good

Well if they were involved in development I'd expect the enclosure to be the right size. But from what you are describing my first guess is definitely that the enclosure for the sub is just too small?

If the enclosure is too small, you'd expect to get no "low" bass, and poor performance (too much or more than expected, causing the cone to distort) of "higher" bass. To put it properly, bass and sub bass. The loads of "higher" bass could easilly end up being too much for the sub as it is able to produce the tones being asked with less excusion than it believes is needed, but the excursion is in any case greater, forcing it to sound as if the signal is going into clip - and making it sound a bit like a wet fart. The lower frequencies would either not be detectable at all or be very quiet.

If the enclosure is too large, you just won't hear very much at all, so it's less likely to be that.

Should you struggle, I'd be tempted to try fitting an IB sub in there still (something that runs independant of a box) or else a lower output sub that requires a smaller amount of space to sound right. The guy in Coventry would know more and I'd definitely take his word over mine though..

Obviously if the issue is that the sub is attempting to overproduce at say the 50-120Hz ranges, then in reality - your "3" setting might be closer to a 7 or 8. In which case the question I have, is - before it starts sounding like shit: Is it loud? I'd exept a decent amount of output ("balanced" with the rest of the setup of course.. IE not enough bass for someone used to installing their own systems) before it clips.

That is, indeed - if I am right about the cause.

But speak to a pofessional, I'm just a part time hobbyist that's done a few google searches when it comes down to it fella..

B&O would have spend 1000's of hours testing this before putting it into a car, I worked with Visteon for a few years developing OEM systems and the R&D extensive even before it saw a car!

It is very hard to diagnose a fault without hearing it but from my experience a common problem with oem bass enclosures is trim panels resonating causing all sorts sound issues, I would have MB check this, maybe a tracker or similar has been fitted in a nearby location (usually all fitted in the same place on these)

Plastic bass enclosures are not the best either as they flex, the actual sub cone is located close to your ears which is not the best scenario, bass waves always work better when it bounced from another surface ie the boot side or rear screen

So what would I do, take it to a respected installer and get them to remove the bass enclosure from its location and test away from the car to determine if its the enclosure or the car, then i'm sure they will be able to rectify it not necessarily changing the equipment but maybe some reinforcement or sound deadening.

Im sorry to hear this, it must be driving you mad as i know you hate the rattles.

I would be extremely surprised if this unit had blown or is clipping, i simply cannot even begin to think you could drive it hard enough within a confined space such as an SLS, so close to your head to generate enough volume to damage the unit or clip it.

I love my audio stuff and have had all sorts of speakers being driven from a valve amp and i've never experienced a blown speaker on a matched system even with ludicrous ear bleeding volumes.

My current system drives so much bass that it makes the candles on top of the speakers rattle and the picture frames on the coffee table rattle to name some things.

I even have a pair of B&O speakers in another room and they can get light unhinged stuff moving at high volume with their integrated subs.

So what i'm saying is, i am more likely to believe the base from them is either causing them to rattle against their housing or the frequencies produced is more likely to make surrounding trim rattle. I guess you could eliminate the housing by removing the sub and holding it but it would be more difficult to isolate a piece of surrounding trim. Sounds like you have a new sub coming your way so that might help remove that from the equation. A simple test might be to press down bits of trim to stop the vibration. I'm completely unfamiliar with an SLS interior and dont even know where the subs are.

Ah damn....why didn't I just think to put on my good ears. You know, the ones I use when I drive the E-Class. That would sort everything

Quote:

Originally Posted by gangzoom

There might not be much info on it because theres not that many SLSs around??

Quite...it's very quiet on the community front, even on the US forums of which the Mercedes (especially C63) ones are very busy. Seems the SLS isn't a car that is bought by people who like to talk about them!

Quote:

Originally Posted by MEGA

Lot's of useful stuff....

Enclosure size...it's the thing that's in the back of my mind. It's also the only explanation I can think of as to why the system I fitted in the Maserati, despite being made up of very high quality components, made an almost identical distortion sound.

Yet what do I know? So, today I spoke to Lee at Platinum in-car as you recommended and, as long as it doesn't come back from Mercedes fixed, I'm taking it to show him at the weekend. He reckons it's a relatively easy challenge!

Quote:

Originally Posted by davyk31

Really can't see enclosure size being a problem, if the manufacturers were involved in development that would be a crazy basic error to make, sounds more like a setup issue to me.

Quote:

Originally Posted by Bomber

B&O would have spend 1000's of hours testing this before putting it into a car, I worked with Visteon for a few years developing OEM systems and the R&D extensive even before it saw a car!

It is very hard to diagnose a fault without hearing it but from my experience a common problem with oem bass enclosures is trim panels resonating causing all sorts sound issues, I would have MB check this, maybe a tracker or similar has been fitted in a nearby location (usually all fitted in the same place on these)

Plastic bass enclosures are not the best either as they flex, the actual sub cone is located close to your ears which is not the best scenario, bass waves always work better when it bounced from another surface ie the boot side or rear screen

So what would I do, take it to a respected installer and get them to remove the bass enclosure from its location and test away from the car to determine if its the enclosure or the car, then i'm sure they will be able to rectify it not necessarily changing the equipment but maybe some reinforcement or sound deadening.

Quote:

Originally Posted by briers

So what i'm saying is, i am more likely to believe the base from them is either causing them to rattle against their housing or the frequencies produced is more likely to make surrounding trim rattle. I guess you could eliminate the housing by removing the sub and holding it but it would be more difficult to isolate a piece of surrounding trim. Sounds like you have a new sub coming your way so that might help remove that from the equation. A simple test might be to press down bits of trim to stop the vibration. I'm completely unfamiliar with an SLS interior and dont even know where the subs are.

But i hope you get it sorted!

To all the above, I'm 99% sure it's not trim rattling - the car is fairly solid in that respect but more specifically, a trim vibration is a totally different sound to the sound of a speaker distorting (as Mega described earlier, like a wet fart!). It's such a specific type of sound that I've heard previously in the system I fitted to my Maserati. That was definitely the sub - with all trim removed, you could see the JL 10W3 sub making the noise! Which was most distressing after I'd spend a considerable amount on some fairly expensive kit!

Lets see what the week brings when Mercedes have finished with it and, if then required, what this specialist that Mega has recommended says. He sounded very knowledgeable on the phone and I was very clear to him on my disappointment from the last time I went down the aftermarket route so, hopefully, he'll be suitably well briefed on my expectations!

Interestingly, what do you guys make of this:

I sent the following complaint to Bang and Olufsen HQ....

I am writing to you regarding the B&O installation in the Mercedes SLS AMG.

Having recently purchased this car, I'm very dissatisfied with the audio quality provided by the system which has the B&O branding, and which B&O claim to have developed for this car. Indeed, so bad is the problem that I initially thought it to be a faulty subwoofer but, having now listened to another example which displays exactly the same characteristics, I can only deem the problem to be typical of the B&O audio system in the SLS.

The characteristic in question is an inability to produce bass at medium volume upwards, without a distortion coming from the subwoofer. This is not a distortion of the surrounding trim; it's more typical of the cone vibrating through either poor design, poor installation or incorrect wiring. Given it's unlikely that two different cars have an identical fault, my fear is that this is not a repairable issue and is in fact how the system has been designed and approved by your company and AMG.

I appreciate quality of sound is subjective and personal however, in direct comparison with listening to the same music and source (320kb MP3 files) on more basic audio systems in other cars, including Mercedes' own unbranded and Harman Kardon systems, the B&O branded systems' inability to produce undistorted bass is unacceptable, especially given the considerable cost of this option.

I would therefore like to understand if you feel this characteristic is typical or whether the audio system has been designed to handle low bass frequencies without distorting. The dealer is unable to do anything other than replace any faulty parts, however, if this is how the audio system is designed to sound then there's unlikely to be any faulty parts to replace. Given this problem is a feature of both examples I've listened to, I find it astonishing that B&O and AMG would sign-off such a poor sound quality from what is a very expensive option and would appreciate your response to this feedback and any remedial action that I could take to improve the performance of this system.

I look forward to hearing from you.

I received the following response this morning, which I read as B&O being totally disinterested in a product which they haven't 'directly' sold or....they and Mercedes actually know it's crap....

Dear Mr Palmer

We are pleased to see you are the owner of Mercedes SLS AMG with Bang & Olufsen sound.

I am sorry to inform you that I can not give you any details regarding your problem. We have been giving strict orders from Mercedes that we can not comment on any questions/complaints. We must refer to the dealer or Mercedes.

Reading between the lines of that it's a known issue which B&O consider to be Mercedes fault

Is the bass actually present despite the noise/distortion? It sounds like a bad enclosure volume and or port - ports can chuff horrible and under damped woffers can bottom out giving the horrible flapping sort of noise

If it comes to it I know a guy who is an acoustic consultant by profession and a petrol head and audiophile by choice. He certainly has the equipment required for a very detailed analysis and a professional report

So, what's next Andrew, surely time to move this on by now . The BOSE system in my Datsun is great .

Does sound odd that B&O are being gagged by Merc. Think if I were B&O I'd be massively questionning my relationship with a company who not only gags me but also doesn't allow me to address issues and therefore damaging the reputation of my company. Sounds odd to me.

We are pleased to see you are the owner of Mercedes SLS AMG with Bang & Olufsen sound.

I am sorry to inform you that I can not give you any details regarding your problem. We have been giving strict orders from Mercedes that we can not comment on any questions/complaints. We must refer to the dealer or Mercedes.

Sorry I was unable to help you, but hope you understand.

Quote:

Originally Posted by two,_OH_five

Reading between the lines of that it's a known issue which B&O consider to be Mercedes fault

+1.

It strikes me as quite a telling email,it's what the message doesn't say,and the sign off sums it up rather succintly.

To me the message comes across along the lines of:

We have never had a problem with our sound systems,and our reputation is one we fiercely guard.
However since signing up with MB,this reputation is becoming sullied,mainly because MB have no clue how to get the best out of our systems,ignored our advice on how best to install our in car audio and use the name B&O to add value to what is already a highly desirable car.

__________________

=================================

Never argue with an idiot on the internet. He will drag you down to his level and beat you with experience.

thats a shoddy response from a company associated with such a valuable asset, and I only agree with what others said. Its a Merc problem, B&O have washed their hands of it.

its disappointing to see that despite the huge premium it takes to obtain a car such as the SLS, it still has its problems. for a car of that value, id expect perfection, and I would imagine you do as well.

however, having read your threads from the past, your a man of means and persuasion - im sure you will reach a satisfactory outcome!